Beach litter deposition at a selection of beaches in the Firth of Forth, Scotland, was studied between July 2001 and December 2003. The amount and types of beach litter is relatively consistent among beaches and over time, with an increased abundance of certain litter types at irregular intervals. Plastic is the most common litter type recorded. The amount of litter items per square metre is affected by Local Authority beach cleaning, community beach cleanings, and the presence of sewerage structures and takeaway facilities. Litter from fishing and shipping was relatively low compared with litter from recreation and sewage-related debris. It is likely that climatic conditions and tidal patterns are the greatest influence on the abundance of beach litter. Management actions are required to effect a reduction in beach litter. A combination of education, provision of adequate waste reception facilities, and enforcement of legislation is needed to tackle beach litter.

Marsh surface deposition, suspended sediment concentrations, tidal hydrodynamics, and marsh surface characteristics were measured within a tidal creek system of a west-central Florida, microtidal, open marine Juncus roemerianus marsh to examine the depositional relationship between a creek system and the surrounding marsh during nonstorm conditions. Results suggest that short-term marsh deposition is highly episodic with deposition showing an inverse relationship with marsh surface inundation. Deposition was greatest at marsh sites adjacent to secondary creek segments over all examined timescales. Variations in hydroperiod, time–velocity asymmetry, vegetation density, and sediment availability could not explain the observed differences in short-term deposition.

Three beach and spit systems have been studied in northern Galicia, along the northwest coast of Spain, within the regional context of sea level rise and coastal erosion. Each system forms part of an estuary's mouth complex within the inner part of the Ortigueira, Barqueiro, and Viveiro rias. Erosive processes along the coast have been characterised and been found to affect cliffs, beaches, and archaeological sites. To compare both long-term (decadal) and short-term (annual) erosion and accretion trends among estuaries, we analysed the morphodynamic characteristics, the degree of human occupancy, and the historical evolution of each system and monitored two profiles at each beach. Dynamic parameters—dimensionless fall velocity and relative tidal range—were calculated for the characterisation of beaches, and maritime climate data—significant wave height (H_s), peak period (T_p), wave fetch direction, and wave period were obtained, and wave height reduction was estimated for all estuaries. Detailed analysis of the three systems shows that, having originated under similar geomorphic and natural dynamic conditions, they have evolved in totally different ways: balance or slight accretion at Ortigueira, erosion at Barqueiro, and strong modification of dynamics at Viveiro. Anthropogenic activity has been identified as the most influential factor, particularly because structures were made without considering the dynamic characteristics of the natural environment in the sites studied.

Within the two major theories of the generation of rhythmic shoreline features, the earlier one relates to edge waves, whereas the one developed later perceives shoreline rhythmic forms as effects of self-organized shoreline behavior. This study focused on identification of infragravity waves (edge waves) and periodic components of shoreline configuration and searched for their potential relationships in the mildly sloping, sandy south Baltic coast. The objective was not to suggest which theory better describes shoreline rhythmic features but was chosen for an empirical assessment of possible links between the generation of rhythmic morphological beach forms and specific infragravity waves motion at a dissipative shore.

The investigated area features a gently sloping seabed with several bars inducing multiple breakers, which can be classified as a dissipative beach. Field measurements were taken during two periods lasting several months each. Long records of water table oscillations, nearshore currents, and measurements of shoreline configurations were analyzed using various signal processing techniques, incorporating traditional spectral analysis and the modern statistical techniques of singular spectrum analysis and discrete wavelet transform.

The measurements revealed two clearly visible infragravity components with periods T_k = 30–40 seconds and T_k = 100–120 seconds at a dissipative south Baltic beach with multiple bars. They were detected by all three methods employed in the study. Additionally, less pronounced components were identified with periods T_k = 180 seconds and T_k = 10–12 seconds. The analysis of variability of the shoreline shape found periodic components with wavelengths ranging between several and several hundred meters and more. Results of this study also suggest that there are links between infragravity waves and rhythmic shoreline forms in a dissipative shore with multiple bars.

Chilika Lagoon (19°28′–19°54′N, 85°06′–85°36′E), on the Orissa coast, India, is one of the world's unique ecospheres. It is the largest brackish water lagoon with estuarine character. Because of its rich biodiversity and socioeconomic importance, it was designated as a “Ramsar site”—a wetland of international importance—in 1981. Interest in detailed analysis of the circulation, biotic, and abiotic factors affecting the lagoon and its limnology is a result of the opening of the new mouth on 23 September 2000 to resolve the threat to its environment from various factors—eutrophication, weed proliferation, siltation, industrial pollution, and depletion of bioresources. This paper describes the development of a two-dimensional depth-averaged hydrodynamic model for Chilika Lagoon and the resulting simulation of currents and salinity corresponding to (i) the Southwest and Northeast monsoon seasons and (ii) pre- and post–mouth-opening conditions. Numerical experiments are performed to understand the different factors—wind, tides and freshwater influx—and their independent and collective roles. Comparison of results obtained with one or both of the openings is made to quantify and validate the changing salinity pattern, which has improved the productivity of the lagoon. Our study shows the salinity levels to be much lower during the southwest monsoon compared to the northeast monsoon, which is validated by observations. The decrease in salinity is attributed to more freshwater influx during the southwest monsoon. There is a significant increase (14%–66%, depending on the sector) in salinity after opening of the new mouth, the maximum change being observed in the channel that connects the lagoon to the sea. The constriction in the lagoon that blocks the tidal effects entering the lagoon is found to be responsible for maintaining the main body of the lagoon with low salinity. The dynamic model will be an important input for our on going work in seasonal study of the ecology of Chilika Lagoon.

Dissolved constituent fluxes from the sediment to the water column are important in estuarine environments. Benthic nutrient source depends on the mechanisms driving advection, the advective transport rate, and the concentration of nutrients in the discharged water, all of which depend on the source of discharged water and water-solid reactions along its flow. Pore water advection has been measured at rates of 3 to 6 cm/d using seepage meters in the Banana River Lagoon, Florida. Diffusion, advection, and reaction modeling of SiO₂ profiles in pore water indicate that advection and reactions are more important than diffusion in the upper 1 m of the sediments. Advection results from the recirculation of the overlying water column through the bottom sediments, oxygenating the lagoon water, while pore water lacks oxygen. As lagoon water recirculates through sediments, the subsequent loss of oxygen enhances regeneration of buried organic matter. Using measured seepage rates and average pore water concentrations of nutrients, N and P fluxes from the sediment are estimated to be 33 to 38 µg/cm²/y and 3 to 5 µg/cm²/y, respectively. On the basis of sedimentation rates and the average concentrations of N and P in the sediment, the fluxes of N and P to the sediment are estimated to be 9 to 38 µg/cm²/y and 2 to 6 µg/cm²/y, respectively. These values suggest that 100% more N and 30% more P may discharge with recirculating lagoon water than is deposited in the sediment. Because the source of most pore water is surface water, the excess nutrients appear to originate from organic matter regeneration at or near the sediment-water interface, thereby elevating their concentrations in pore waters and depleting their concentration in the buried sediment. This regeneration of nutrients appears to limit their burial rate in the lagoon.

A methodology for monitoring long-term beach face volume change with a combination of intermittent profiling and video imagery is developed. Intertidal beach morphology can be mapped from video with the use of movement of the waterline over a tidal cycle. Such maps provide detailed information on spatial and temporal evolution of the intertidal area, but no direct information on beach face volume changes as a whole. However, beach face volume might well be correlated with cross-shore changes to a contour located in the intertidal zone. This is significant because such a parameter can be calculated from maps of the intertidal morphology generated with video images. This idea was tested with a series of video images and surveys that were collected over a year and a half on an intermediate beach on the Coromandel Peninsula, New Zealand, over a wide range of conditions. The surveyed profiles show a strong (r² = 0.95) relationship between the surveyed cross-shore location of the 2-m contour and the surveyed beach face volume, indicating that beach face volume changes are due mostly to intertidal changes. The relationship (r² = 0.91) between the cross-shore location of the 2-m contour line derived from video and that derived by survey is also strong, demonstrating that the resulting regression parameters can be used to derive beach face (not just intertidal) volume from video. This relationship is unlikely to be universal and must be calibrated with standard (albeit infrequent) profiling at each specific site. The final relationship allows the video images to be used to predict changes to the beach face volume with a success rate of 89% for the test beach used. Such a model is the first step toward providing a robust remote method to coastal managers for assessing day-to-day variations in beach face volume over multiple profile lines on the same beach.

Macrofaunal communities of beaches in eastern Australia were investigated for relationships of species number, abundance, and biomass with the physical characteristics of the beach environment (expressed numerically as the dimensionless fall velocity and beach state index [BSI]). A range of physical beach states across three biogeographical regions was sampled for macrofauna at low tide during summer months, and the data were regressed and compared. Results showed that species number, abundance, and biomass increased from reflective to ultradissipative shore conditions (abundance and biomass increasing logarithmically). Species number showed the same numerical relationship with BSI for each of the regions studied, the common regression equation showing that nearly 90% of variation in macrofaunal species number between beaches can be explained by this compound index of physical parameters. Abundance and biomass showed similarities in response to BSI, although at different orders of magnitude by region. The results of a multiple regression including latitude suggest that, although species richness is almost directly related to physical beach processes, abundance and biomass are determined more by a combination of surf zone processes and climatic factors specific to each biogeographic region.

A coherent approach to structuring reference units for coastal vulnerability analysis is often required for large-scale analyses of the coastal system. However, a review of existing spatial reference frameworks within vulnerability analyses demonstrates that our use of coastal space within large-scale models remains relatively poor. This paper examines a series of challenges to spatial modeling that have emerged from the development of a national to global impact tool, DIVA (Dynamic Interactive Vulnerability Assessment). The paper addresses how best to utilize the limited data to develop a reference framework for modeling vulnerability within the global coastal environment. It outlines the approach to spatial modeling that has been developed for use within the DIVA tool: segmenting the coastal zone into a series of relatively homogenous reference units at the scale of DIVA, based on the behavior of the physical, social, and economic systems within the zone. The importance of effective spatially defined models is emphasized within the paper. Encouraging greater spatial recognition and definition of the behavioral environment of the coast is critical to modeling space within the coastal system. By decreasing spatial uncertainties in the creation of reference units for vulnerability analysis, the accuracy of modeling within large-scale coastal environments can be further improved.

The north Chennai coast, on the east coast of India, experiences severe erosion caused by waves, and an area of the beach about 600 m wide has eroded over the past 120 years. To protect the seafront, natural stones were dumped by government agencies along the coast for a distance of about 6 km, and in the process, a short beach pocket 400 m long was left unprotected for various reasons. Because the property of a chemical factory located in this 400-m stretch of beach pocket suffered damage caused by erosion, and because the need for a wide beachfront was stressed by local fishermen, an alternative method of protecting the beach was suggested. The proposal involved construction of an S-type rubble sea wall about 100 m long on the southern end of the beach pocket. This paper discusses the numerical model studies conducted to determine the configuration of the S-type rubble sea wall and its effectiveness in beach protection. The model studies suggested a length of projection of 14 m with a radius of curvature of 310 m for the S-type sea wall to achieve the desired performance. Field studies conducted on the 40-m-wide and 400-m-long beach pocket with the 100-m-long S-type sea wall indicate that the sea wall is effective in protecting the beach.

The São Francisco River mouth is undergoing a severe erosional process that has caused the destruction of a village and the partial immersion of a lighthouse constructed in 1856. The present work comprises an historic time evaluation of this phenomenon based on the analysis of the sediment dispersion patterns caused by waves along three distinct shoreline traces. For this, we define a wave climate model based on the construction of refraction diagrams, which are assumed to be valid for the three shorelines. The resulting sediment transport patterns obtained by numerical modeling from the refraction diagrams—taking into account the angle of approach and the wave height along the coast—allow us to establish a first-order correlation between coastal dynamics and erosion phenomenon. The results also suggest that a permanent reduction in the solid river discharge, in response to the construction of large dams, probably will have two direct consequences in the river mouth region: (i) a chronic shoreline erosion downdrift of the mouth and (ii) a progressive deflection of the mouth in the downdrift direction.

Successful development and management of coastal zone infrastructure is to a great extent based on proper estimates of current and future wave conditions. In this paper, a site-specific artificial neural network methodology is proposed to serve as a basic tool for both now and forecasting of wave parameters in variable coastal environments. This tool is an alternative to data and computational effort demanding deterministic wave models. The data used were collected during a field campaign near the Tasmanian coast. The campaign was undertaken to estimate sea states and temporal variability of wave conditions in the Tasmanian region. This study is considered to be a logical extension of that campaign. These data were used in a neural network study for the first time. The periods under consideration differ for different sites and extend from September 1985 to December 1993. The quality of the neural simulations was assessed vs. the independent measurements in terms of the bias, root mean square error, correlation coefficient, and scatter index. Neural networks of three different architectures perform in a similar way and produce reliable predictions 3 and 6 hours ahead. The accuracy drops for larger warning times. Meanwhile, the tracking and retrieval of wave parameters exhibit stable, high quality. Thus, the results show the feasibility of the methodology for wave forecasting and data supplementation in essentially different topographic conditions.

Coastal erosion is an islandwide problem in Taiwan. On the basis of the result of the most recent survey, more than 80% of the island's sandy coasts have undergone erosion over the past 3 decades. Naturally and historically with the specific tectonic environment and uplifting rate in Taiwan, sufficient sediments had been yielded and transported to the coastal area, resulting in an advancing shoreline along the trailing edge coast during the last several centuries. However, human interventions have contributed significantly to the erosion in more recent times. In this paper, documented examples are chosen to address how human-induced changes have made profound impacts on the coastal erosion in Taiwan. The information presented will provide a better understanding of the coastal processes, and solutions to the erosion problem for the benefit of others in different parts of the world.

The Xisan Tidal Furrow appeared as early as 1976. The major dynamic factor in the formation of the Xisan Tidal Furrow is the increase in the flood-tidal level near Xisan Gate and the extension of beach face accretion in An'dong, both of which originated from large-scale human activities. The inlet position of the Xisan Tidal Furrow has experienced four stages, i.e., swinging, stabilizing, moving eastward, and stabilizing, while the series furrow at the outside beach face is the main cause of the change in the scouring and silting of the Xisan Tidal Furrow. This article explains the causes of the Xisan Tidal Furrow's formation and its evolution, and proposes the guideline of “regulating the furrow and reclaiming the tidal flats by making the best use of local topography.” On one hand, the river channel direction must comply with the regular pattern of the stream current and of sediment movements. On the other hand, furrow regulation and reclamation of tidal flats along the riverbank should be combined. We suggest that fill stone should be used and a rock dam built to completely cut the Xisan Tidal Furrow; this should occur when the Qiantang River basin has a wet year.

Assessment and monitoring activities constituted two main tasks of the emergency response system implemented by the regional government of Cantabria (north Spain) after the Prestige oil spill. The assessment covered four types of environmental units: estuaries, rocky shores, sand beaches, and subtidal areas, up to a 300-m depth. Monitoring procedures included the chemical quantification of total hydrocarbons and polycyclic aromatic hydrocarbons in water, sediments, and benthic organisms (clams and goose barnacles), and the analysis of structural changes in intertidal communities.

Disturbance of oil cover was significantly more extensive in coastal areas, rather than in estuarine areas, where 50,000 m² were directly covered by fuel. Otherwise, the presence of oil in subtidal areas was a rare event. Results from the bioeffects analyses were in agreement with the overall impact assessments, pointing to the coastal habitats as the areas where the bioavailability of toxic components from the Prestige spill presented a significant level of risk.

The Maspalomas dune field and adjacent beaches are the most extensive coastal sedimentary environment on the island of Gran Canaria. This area is very important from both a natural and an economic perspective. The analysis of aerial photographs and satellite images from recent decades does not show important shoreline changes for the El Inglés and Maspalomas beaches, which can be considered, consequently, in a state of equilibrium. However, the Maspalomas dune field presents several modifications, such as aeolian corridors associated with beach kiosks, a significant reduction in thickness of the aeolian deposits, and an increase of deflation areas in the underlying substratum. All these are proof of a drastic reduction in sediments.

Sediment transport pathways obtained from the grain size parameters of beach samples show an input of sediments from El Inglés beach to Maspalomas dune field, whereas longshore drift is predominant on Maspalomas beach. This grain-scale analysis agrees with previous geomorphologic and wind studies. Foraminiferal content analysis also confirms the input of sediments from El Inglés beach to the dune field, as well as indicating the lack of inputs across Maspalomas beach, on which only seaward fluxes from closer dunes can be expected.

Input and sinking areas of the system have been confirmed as well as a notable lack of sediments in the dune area, which is suffering severe erosion because of the shortage of sediment supplies from El Inglés beach.

Year-round nitrate measurements over a 16-year period from precipitation, groundwater, two harbors, Cape Cod Bay, and Buzzards Bay have been analyzed for their long-term nitrate cycles and correlations. Cyclic behavior in annually averaged nitrate concentration at variable amplitude and periodicity was observed in both estuaries, in the bays, and in the groundwater. These five nitrate concentration time series had correlations of 0.7 or larger among themselves and, except for Cape Cod Bay, with the annually averaged water table height upgradient of the two harbors. The low-frequency water table height variation explained 50% or more of the harbor nitrate variability. The nitrate concentrations were also correlated with the averaged wintertime precipitation amount in the area that had similar multi-year variability. These low-frequency correlations were found to be regional in nature and were thought to be from changes in hydraulic head caused by climatic scale changes in precipitation and infiltration. This was likely driven by changes in the winter hydrological cycle and was decoupled from seasonal scale events. The contribution that the new data in this study make comes from their regular sampling intervals, extended duration, and analyses at climatic scales.

In this study spectral and cross-spectral analysis are conducted using the complex Morlet wavelet transformation to investigate wind–wave interaction during wave growth. The wavelet power spectrum of the individual time series of wind speed and wave height shows that the energy content of these time series varies considerably with time for different scales. The cross-spectrum shows that the energetic events in the wind and wave time series occur at the same scale and time. Therefore, the use of wavelet analysis gives the ability to analyze features that could not be analyzed through the use of the classical Fourier analysis because of the nonstationarity feature of the wind speed and wave height signals. The computed cross-spectrum shows that the regions of high values correspond to the occurrence of a sudden increase in wind speed or wave height.

Hydrodynamics, sediment suspension, and morphological response on an estuarine intertidal sand flat in Tokyo Bay, Japan, are examined through a field experiment performed for 16 days in winter 2000 and using a bathymetry data set based on a 6-year series of surveys. Topography of the sandy flat was found to fluctuate by approximately 8 cm during the deployment, while the long-term accumulation rate is estimated with the surveyed bathymetries to be only 3.8 cm/y. Cross-spectral analysis of the measured data indicates that on the sandy tidal flat, semidiurnal or shorter-period fluctuations in current velocity are mostly attributed to semidiurnal tides and waves, whereas wind above the sea generally drives diurnal or longer-period fluctuations. The field data also confirm that suspended sediment concentrations were highly correlated with bed shear stress, which is generated by combination of tidal current, wind-induced current, and wind waves. Episodic erosion is observed on the sandy flat with high turbidities on ebbing phases. Erosion evidently occurs at phases between the high slack and the mean tidal levels during ebb flows when combined tidal, wind-driven, and wave-driven currents are maximized.

This study was undertaken to establish the most reliable breaker depth index formula that will yield satisfactory predictions for a wide range of hydraulic and beach conditions. The applicability of six existing formulas for computing the breaker depth index was examined with the use of a large amount of published laboratory data (524 cases collected from 22 sources). The behavior of these formulas was studied with respect to the main governing parameters, which are the beach slope and the deep-water wave steepness. It was found that most formulas show quite good predictions for cases including gentle slopes (0.01 < m ≤ 0.07). However, the predictions are typically not satisfactory for breaking waves on steep slopes (m > 0.1), and the formulas do not always present a physically correct behavior with respect to the two main parameters. A new formula is proposed to predict the breaker depth index with the best possible accuracy. Also, a discussion is included on the application of the formula to random waves and on the relationship between the breaker depth index and the Irribaren number to distinguish between different breaker types.

The eastern Acheloos River delta and the Lagoon of Etoliko have undergone broad environmental changes since the mid-Holocene. In this study, sedimentological, geochemical, geophysical, micromorphological, computer tomographical, micro- and macrofaunal, and archaeobotanical methods were applied to determine lateral and vertical facies patterns of near-coast geological archives. We present the stratigraphic sequences of 13 vibracores and one 9-m-long sediment core from the Lagoon of Etoliko. Geochronology was based on 28 radiocarbon dates. Sea-level fluctuations were detected by means of sedimentological sea-level markers. The relative sea level rose from 12.70 m below sea level (b.s.l.) at 6150 cal BC to 7.90 m b.s.l. by 4750 cal BC and 2.60 m b.s.l. by 500 cal BC. The maximum rate of rise occurred until 5550 cal BC, and the lowest, between Helladic and Byzantine times. Delta growth clearly increased after the relative sea-level rise decelerated around 5500 cal BC. Palaeogeographical maps for different points in time are presented here. During the Last Glacial Maximum, a freshwater lake existed in the Etoliko basin. At 4750 cal BC, the Acheloos River delta had already crossed the Paracheloïtis lowland pass and prograded into the Lagoon of Mesolongion, which was closed off from the sea by a barrier system. At 3600 cal BC, a distributary broke into the Lake of Etoliko. Progradation of a large deltaic plain toward the southeast took place until 1550 cal BC. Then, direct river water inflow into the Lake of Etoliko ceased. Circa 1200 cal BC, the river was definitely redirected toward the western part of the delta, and ongoing relative sea-level rise, possibly associated with coastal erosion, connected the Lake of Etoliko to the Lagoon of Mesolongion. Since then, the delta plain has undergone further submergence. Geoarchaeological aspects are also discussed with regard to the palaeogeographical evolution of the area.

This paper describes a study of Trieste sea level data for the period 1875–1914. Monthly sea level means for 1875–89 and 1901–04 are here reported and analysed for the first time after their original publication. This increases the length of one of the few Mediterranean records spanning more than a century. Trieste data are quality controlled by comparison with those of other stations in the northern Adriatic, and several monthly values that differed from that shown by the reference stations were detected. An explanation for the suspect data is difficult because of the absence of detailed information on the tide gauge operation. The discrepancies probably are due to instrumental problems. The completeness of the data that make up the monthly means does not seem to play a significant role. The addition of data to the previously known record does not affect the long-term linear trend estimate, which turns out to be 0.13±0.01 cm/y for both the old and the updated time series.